A Story Outline of Evolution 



minated In the form of the modern horse. These primitive 

 ancestors probably deserted the forests and jungles In order 

 to escape their jungle enemies or, perhaps, the scanty stunted 

 herbage of these plains produced a more satisfying food, but 

 in any event, there was no necessity for so many toes. The 

 middle finger or toe began to increase in length and the toe 

 nail to increase in size. This process continued throughout 

 vast periods of time and the other toes began to atrophy 

 and to be cast off. The horse now walks on its middle toe 

 and its toe nail has developed into a hoof. But Nature does 

 not cast off the work she has done through long periods in 

 a single day. She uses, perhaps, as much time in the destruc- 

 tion of an organ as she did in its creation. The evolution- 

 ary process of casting off the unused toes is still at work. 

 The little hoof like appendages on the inner sides of the 

 horse's legs near the knee joints are simply the rudimentary 

 toe nails of a toe that has been cast off for a lack of use and 

 Nature has not quite finished the work of removing the toe 

 nails. A corresponding change has taken place in the teeth 

 to meet the changes in the character of their food obtained 

 upon the plains. The contemporary ancestors of most of the 

 quadrupeds, perhaps all of them, have modified their teeth 

 to meet the changing conditions and character of the food 

 that gives nourishment to their bodies. The compulsion of 

 hunger must be satisfied if life continues to exist. When a 

 food which has been used, either through necessity or choice, 

 for a long period of time Is no longer obtainable, then the 

 animal using this food must change its diet and adapt Its body 

 organs to the use of the new food or perish. Nature, in 



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